Desiderosmia-Associated Iron Deficiency: A Case Report and Review of the Literature.

Iron deficiency is the most common cause of anemia worldwide, yet desiderosmia remains rarely described as one of its manifestations. The term "desiderosmia" was first proposed in a case series by Hansen et al. to describe compulsive olfactory cravings for specific scents observed in three symptomatic patients with iron deficiency, derived from the Latin word "desiderare" for desire and the Greek word "osme" for smell. Desiderosmia appears to be closely related to pica, a common manifestation of iron deficiency, though the key difference is that patients report olfactory cravings without the desire to consume the scent-producing substance. As far as the authors of this report are aware, the number of published cases of desiderosmia is extremely scarce, and the term itself has yet to become recognized in medical literature, owing to its novelty. We report the case of a 32-year-old woman with menorrhagia and iron deficiency anemia (IDA) refractory to oral ferrous sulfate despite adherence. Despite her hemoglobin improving from 9.1 to 9.9 g/dL (reference range: 12-15.5 g/dL), her ferritin remained critically low at 1 ng/mL (reference range: 30-400 ng/mL). At that time, she developed an intense urge to smell pine-scented cleaning products, alongside migraines and restless leg syndrome, hypothesized to be neuropsychological symptoms linked to altered CNS iron homeostasis. We speculate that desiderosmia may share a similar neurological mechanism, correlating more closely with the severity of iron store depletion rather than with anemia severity. Recognition of this symptom prompted identification of IDA not improving with oral iron and escalation of therapy to IV ferrous carboxymaltose. Following treatment with intravenous iron repletion, her ferritin increased to 52 ng/mL, and she no longer experienced desiderosmia or any other iron deficiency symptoms. This case highlights the need for validating studies of desiderosmia's potential as a diagnostic marker in cases of severe iron deficiency and the symptom's pathophysiology.